The excrementitious matter has long been used as efficatious fertilizer since old times; but it is now being disfavored because of its offensive odor and inconvenience in handling due to the fluidity of the matter. Various attempts have now been made to deodorize and solidity the filth materials for easy handling. One example of such filth-treatment apparatus is such as is given in the followings.
The material to be treated is first separated into solid components and liquid components, namely, feces and urine in a storage tank; the feces are pulverized in a pulverizing tank, and subsequently transfered to an electrolysis tank where it is mixed with the urine and electrolyzed after adding sodium sulfate and ferric oxide in order to deodorize the material. The resultant products are then added with pottasium silicate to enhance the viscosity, and finally dried to cakes by a drying means.
Thus, such systems wherein the filth material is deodorized by electrolysis requires dilute suspentions containing considerably larger amount of liquid components because a sufficient amount of electric current must be applied in order to deodorize the material. Consequently, it becomes necessary to mix a large amount of unfertilizable diatomite into the suspension at the drying stage in order to recover the viscosity once lost by dilution. Moreover, since the excrementitious matter contains a number of organic nonelectrolytes, the electrolytic method can furnish only insufficient deodorization. It is especially inappropriate when applied to treatments in an industrial scale, because it requires a great amount of electricity only to achieve some insufficient degree of deodorization. Furthermore, the fertilizability of the products is impaired by addition of large amount of diatomite which is completely innutritious to plants.
One of the object of the present inventin is to provide a new filth-treatment apparatus wherein the filth material is converted, as well as deodorized, to a fertilizer having greater fertilizability than the naturally aged manure due to the powdered basic rocks, having a selected composition and particle size, mixed into the filth material. On the other hand, there is another category of filth-treatment technology in which the reutilization of the product is not intended. One of such method is the well known activated sludge process, wherein the malodorants in the filth are biologically decomposed by the activity of living organisms such as bacteria.
The method according to the present invention is based upon a chemical method, as opposed to the above biological activated sludge process, wherein the acid malodorants are chemically neutralized by basic agents.